Surface modification of a polyhedral oligomeric silsesquioxane poly(carbonate-urea) urethane (POSS-PCU) nanocomposite polymer as a stent coating for enhanced capture of endothelial progenitor cells

Abstract

An unmet need exists for the development of next-generation multifunctional nanocomposite materials for biomedical applications, particularly in the field of cardiovascular regenerative biology. Herein, we describe the preparation and characterization of a novel polyhedral oligomeric silsesquioxane poly(carbonate-urea) urethane (POSS-PCU) nanocomposite polymer with covalently attached anti-CD34 antibodies to enhance capture of circulating endothelial progenitor cells (EPC). This material may be used as a new coating for bare metal stents used after balloon angioplasty to improve re-endothelialization. Biophysical characterization techniques were used to assess POSS-PCU and its subsequent functionalization with anti-CD34 antibodies. Results indicated successful covalent attachment of anti-CD34 antibodies on the surface of POSS-PCU leading to an increased propensity for EPC capture, whilst maintaining in vitro biocompatibility and hemocompatibility. POSS-PCU has already been used in 3 first-in-man studies, as a bypass graft, lacrimal duct and a bioartificial trachea. We therefore postulate that its superior biocompatibility and unique biophysical properties would render it an ideal candidate for coating medical devices, with stents as a prime example. Taken together, anti-CD34 functionalized POSS-PCU could form the basis of a nano-inspired polymer platform for the next generation stent coatings.

Plasma Surface Modification of Polyhedral Oligomeric Silsequioxane-Poly(carbonate-urea) Urethane with Allylamine Enhances the Response and Osteogenic Differentiation of Adipose-Derived Stem Cells

“…41 Following plasma polymerization a drop in WCA was observed for all the samples, suggesting improved wettability of the polymer. Wettability plays pivotal role in cell-materials interactions.…”

Next generation covered stents made from nanocomposite materials: A complete assessment of uniformity, integrity and biomechanical properties

“…As mentioned previously, POSS-PCU has a proven potential in various biomedical application including cardiovascular implants 15,35,36 . In this study the non-thrombogenicity of POSS-PCU was compared to ePTFE and CoCr BMS, which are common candidates of materials of synthetic covered stents in the market 4 .…”

The Quest for Nonthrombotic Surface Modifications to Achieve Hemocompatibility of Implantable Devices

“…PoSS-PCu has been functionalized by covalent linkage to endothelial progenitor cell (EPC)-specific antibody (anti-CD34) that attracts EPC leading to endothelialization, which prevents thrombosis (Figure 7). 95 There is some evidence that it is a biocompatible material because it was used as a scaffold for a tracheobronchial transplant in a 36 year old male patient with tracheal cancer. 96 Further data on thrombogenicity come from in vitro studies where polyvinyl chloride (PVC) spray coated with PoSS-PCu then functionalized with anti-CD34 that showed hemocompatibility.…”